Carton opening hand tool



Aug. 25, 1970 A om ET AL 3,525,152

CARTON OPENING HAND TOOL Filed May 14, 1968 mar M ,1, 5 r a Z n oJ L d .2 F3 0 2 1 1 Vi w 3 7 l I 0 1 P W v w a H e H l F \w C m INVENTOR.

LAZZARO A. FATTORI- FRANK BlS CONE ATTORNEY United States Patent 3,525,152 CARTON OPENING HAND TOOL Lazzaro A. Fattori, 84 Rose Ave., Woodclilf Lake, NJ. 07680, and Frank Biscone, 53 Schumacher Drive, New Hyde Park, N.Y. 10040 Filed May 14, 1968, Ser. No. 729,043 Int. Cl. B67b 7/30 US. Cl. 30-2 6 Claims ABSTRACT OF THE DISCLOSURE A razor blade holder molded of a resinous plastic serves as a hand tool and has a top wall over-hangingly projecting beyond a beveled end wall providing a reentrant corner to engage and be drawn along the top edges of a corrugated carton. A razor is positioned against a bottom wall of the holder and has an edge projecting through a slit in the beveled end wall for cutting a sidewall of the carton at a spaced distance from the carton top surface determined by the spacing of the slit from said projecting top wall of the tool. The bottom wall has means including indicia for adjusting the depth of cut of the razor to difierent carton wall thicknesses.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a simple hand cutting tool and more particularly is directed to a razor blade holder having guide means positioning the blade for severing tops from corrugated cartons.

Description of the prior art It is the practice in supermarkets and other stores to open corrugated shipping cartons by cutting the sidewalls just below the top wall to remove the latter completely or to cut only three of the sidewalls for folding back the top in flap fashion. Thus, there is a need for a simple, inexpensive hand tool to serve as a handle or holder for a single edge razor blade, which provides the cutting edge, to incorporate guide means to facilitate the cutting along a straight line at the proper distance below the carton top to clear the double flaps thereof, and to provide means for adjustably controlling the depth of cut of the blade to meet different carton wall thickness requirements and also limit the depth of cut to insure against damage to the contents which may be a product packed in relatively thin wall, easily slit cardboard boxes.

SUMMARY OF THE INVENTION Among the objects of the invention is to provide a hand tool utilizing a conventional single edge razor blade for its cutting edge, which too] shall meet the need as hereinbefore described. The hand tool shall comprise few and simple parts which are relatively inexpensive to manufacture in quantity production of resinous plastic material by injection molding methods and easy to assemble with a standard nut and bolt fastener which also serves as part of a depth of cut adjustment means. The tool comprises a substantially rectangular shaped box of hand grip size and a razor blade retaining and indexing plate fitted to the bottom wall of the box with the razor blade therebetween. One end wall of the box is beveled with respect to the opposite end wall and has a slit formedtherein at the bottom of the box through which a corner 3,525,152 Patented Aug. 25, 1970 of the razor blade extends. A flange extending from the beveled wall at the top of the box provides a reentrant corner for engaging a top edge of a carton to guide the projecting blade along a predetermined path for cutting the carton side walls spaced below the carton top edge. The flange may be triangular in shape to complement the angle of the beveled side wall providing a squared-off edge to which a cover for the box may be integrally hinged. An indexing means on the retaining and indexing plate is visible through a longitudinal slot in the box bottom wall for selective alignment with indicia designating various carton wall thickness whereby the razor blade is adjusted for the desired depth of cut. The hand tool shall be rugged in construction, foolproof in operation, serve as a recep tacle for new and used razor blades, and permit full retraction of the blade for safety when not in use.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of the carton opening hand tool embodying the invention shown applied to an upper edge of a corrugated carton and cutting a side wall thereof.

FIG. 2 is a bottom" plan view of the hand tool shown in FIG. 1, but with the integrally hinged top cover shown spread fiat in open position and bolt fastener shown in section.

FIG. 3 is a longitudinal sectional view of the hand tool as seen on line 3--3 in FIG. 2, the hinged top cover being indicated in closed position in broken lines.

FIG. 4 is a sectional view taken on line 44 in FIG. 3 but with the cover closed, and

FIG. 5 is a bottom plan view view of the retaining and indexing plate removed from the assembly showing details of the razor blade facing side thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring in detail to the drawing, 10 denotes a carton opening hand tool constructed to embody the invention seen to comprise a box 11 of hand grip size containing a retaining and indexing plate 20 for a single edge razor blade 24 adjustably fastened therein by screw 21. lock washer 22 and thumb nut 23.

Box 11 has a bottom wall 12, a beveled end wall 13, a long side wall 15 paralleling a short side wall 16, and an end wall 14 perpendicular to side walls 15, 16. A flange 17 extends from the upper end of beveled end wall 13 forming a reentrant corner therewith spaced a predetermined distance from a slit 13a in wall 13 adjacent bottom wall 12. A longitudinally extending slot 12a is provided in bottom wall 12 centralized with respect to side walls 15, 16.

Bottom wall 12 and retaining and indexing plate 20 are herein shown constructed to accommodate therebetween single edge razor blade 24 of conventional construction, that is, having a reinforced edge portion 24a opposite the cutting edge 24b, a recess 24c at the center of each of the side edges and a center slot 24d. Bottom wall 12 has its interior surface stepped to provide a depression into which razor edge portion 24a fits. The plate 20 fits between side walls 15, 16 and is formed with an opening 20a centralized to align with bottom wall slot 12a and razor slot 24d for receiving screw 21 therethrough. A boss 20b, located at an end edge of plate 20 adjacent end wall 14, extends from a razor blade facing side 20e into bottom wall slot 12a. Boss 20b aligns withand is spaced from opening 20a and is sizedand shaped to engage the recess 24c on the inner side edge of razor blade 24 when in assembly in box 11. The opposite end edge of plate 20, that is, the end edge adjacent beveled end wall 13, is formed with a corresponding beveled corner 20d beyond which a corner of razor blade cutting edge 2412 projects through slit 13a in wall 13.

The surface of boss 20b visible in slot 12a may be provided with an index means such as line 200 or an arrow head for selectively aligning plate 20 and razor blade 24 carried thereby with a scale located along an edge of slot 12a and having lines designated A, B, C and E, respectively, which letters correspond to conventional wall thickness designations of corrugated cartons. Alignment of index line 200 with the desired designation on the scale sets the projecting razor blade 24 for the proper depth of cut.

Box 11 and plate 20 may be injection molded of any suitable resinous plastic. For the illustrated embodiment, box 11 may be made of linear polyethylene, polypropylene, or the like material having tough foldable tear resistant properties satisfying the requirements for an integral hinge or pivot. Although box 11 in a crude form may be left open or fashioned with any suitable cover, to combine the advantage of more economical production cost with desirability of a hinged cover, box 11 has a cover 18 integrally hinged along foldable web 19 to flange 17, the latter being substantially triangular in shape to complement beveled end wall 13 and dispose foldable web 19 in parallel relation to end wall 14. To provide a snug fit for cover 18 on box 11, a long rib 18a and short rib 18b extends longitudinally along the interior surface of cover 18 and are positioned to abut long side wall 15 and short side wall 16, respectively, when cover 18 is closed. An integral latch 18c extends from cover 18 and engages an undercut 14a formed in end wall 14 releasably retaining cover 18 in closed position. To facilitate opening, cover 18 has a finger lift tab 18d protruding slightly beyond end wall 14. In molding box 11, slit 13a may be fashioned simply by beveling the edge between bottom wall 12 and beveled end wall 13 as is clear from FIGS. .2 and 3.

The operation and practical utility of carton opening hand tool will now be apparent. Assembly is readily accomplished by placing a single edge razor blade 24 in open box 11 so that reinforced edge 24a lies in the depression formed therefor in bottom wall 12. Retaining and indexing plate 20 is then placed over razor blade 24 so that boss 20b, facing downwardly, lies in slot 12a and engages the recess 240 in the side edge of razor blade 24 adjacent end wall 14 and opening 20a aligns with razor blade slot 24d. Bolt 21 with lock washer 22 thereon is then inserted through opening 20a and razor blade slot 24d to project through bottom wall slot 12a and have thumb nut 23 threaded thereon. Hinged cover 18 may then be folded over and snapped into closed position.

Razor blade 24 is selectively positioned either to be fully retracted when not in use or to project through slot 13a by slightly loosening thumb nut 23 and moving the latter along slot 12a. Selection of a desired depth of cut may be aided by aligning index line 200 with the appropriate carton wall thickness letter designation on the scale provided on bottom wall 12 adjacent slot 12a. Thumb nut 23 is then tightened to lock plate 20 and razor blade 24 in the selected position.

With razor blade 24 set for the desired depth of cut, hand tool 10- may be grasped in the right hand as indicated in FIG. 1 and the reentrant corner between flange 17 and beveled end wall 13 placed against a top edge of the carton to guide the projecting edge of razor blade 24 in cutting the carton side Wall in a straight line at a spaced distance below the top edge as tool 10 is drawn therealong.

To replace razor blade 24, top cover 18 is readily opened by inserting a finger nail under lift tab 18d and thumb nut 23 removed from bolt 21 thereby releasing plate 20 for access to razor blade 24. Tool 10 is then reassembled with 4 a new razor blade 24 in the manner hereinbefore described.

We claim:

1. A carton opening hand tool comprising an elongated hand grip sized box defining a chamber in part formed by a movable top wall, a bottom wall for receiving a razor blade thereagainst spaced from said top wall and a bevelled end wall extending between said top wall and said bottom wall, said end Wall being formed with a slit adjacent said bottom wall for projection of a corner of the razor blade therethrough, a flange extending from said end wall at a spaced distance above said slit formed in said end wall providing a reentrant corner to engage and be drawn along a top of a carton thereby determining the cutting depth of the razor blade projecting through said slit, said top Wall being movable between an open and closed position, said bottom wall only being formed with an elongtaed slot in alignment with a central slot in the razor blade, and means extending through the central slot in the razor blade and through said elongated slot for releasably positioning the razor blade along said slot for varying the extent projection of the blade through said slit.

2. A tool according to claim 1, wherein a retaining plate overlies said razor blade for movement longitudinally therewith, said plate being formed with an opening and having a boss extending beyond said blade and into said slot formed in said bottom wall.

3. A tool according to claim 2, wherein said releasable positioning means comprises a bolt extending through said opening in said plate and through said slot in said razor blade and said longitudinal slot in the bottom plate and a thumb nut terminating said bolt for releasably securing said razor blade and plate assembly in a selected position along said slot.

4. A carton opening hand tool comprising a hand grip sized box having a bottom wall sized to receive a razor blade thereagainst and a beveled end wall, the latter having a slit adjacent said bottom wall for projection of a corner of the razor blade therethrough, a flange extending from said end wall at a spaced distance above said slit providing a reentrant corner to engage and be drawn along a top edge of a corrugated carton thereby determining the cutting path of the razor blade projecting through said slit on the carton side wall, a retaining plate overlying said razor blade for movement longitudinally therewith, said plate being formed with an opening and having a boss extending beyond said blade and into said slot in said bottom Wall, and means extending through a slot in the razor blade and through said longitudinal slot for releasably positioning the razor blade along the slot for varying the extent of projection of the blade.

5. A tool according to claim 4, wherein index means is provided on said boss, a scale along an edge of said slot for selective alignment with said index means for adjusting the extent of projection of the razor blade through said slit to control the depth of cut, said releasable position means comprising a bolt extending through said opening in said plate and through said slot in said razor blade and said longitudinal slot in the bottom plate and a thumb nut terminating said bolt for releasably securing said razor blade and plate assembly in a selected position along said slot.

6. A carton opening hand tool comprising an elongated hand grip sized box defining a chamber in part formed by a movable top wall, a bottom wall for receiving a razor blade thereagainst spaced from said top wall and a beveled end wall extending between said top wall and said bottom wall, said end Wall being formed with a slit adjacent said bottom wall for projection of a corner of the razor blade therethrough, and a flange extending from said end wall at a spaced distance above said slit formed in said end wall providing a reentrant corner to engage and be drawn along a top of a carton thereby determining the cutting depth of the razor blade projecting through said slit, said box being molded of an elastomeric resinous material and said flange being 2,238,753 4/1941 Robie 30 2 connected by an integral hinge to said top Wall for the 2,282,697 5/1942 Bates 302 box, said top wall having an integral latch adjacent the 2,814,864 12/1957 Zevely et a1. 30-2 edge opposite said hinge for releasable snap-in engage- 2,840,903 7/1958 Christensen 302 X ment with an undercut in a Wall of said box. 2,884,155 4/ 1959 Hanson.

5 3,259,978 7/1966 Weichselbaurn 3059 References Cited UNITED STATES PATENTS LESTER M. SWINGLE, Primary Examiner 2,081,361 5/1937 Marshall 30-283 G- RAFEL, Assis ant Ex miner 2,187,590 1/1940 Lurie 302 10 

